body {
    //以下四行代码作用是完美适配所有屏幕
    background-image: url("../img/advertisement-bg.jpg");
    //这是需要设置得比所有屏幕都大
    background-size: 1280px;
    background-repeat: no-repeat;
    background-position: top center;
}

header {
    width: 100%;
    height: 44px;
    font-size: 16px;
    color: #000;
    line-height: 44px;
    text-align: center;
}

main {
    position: relative;
    flex: 1;
    text-align: center;

    //  < !-- 跳过按钮 -->
    .skip {
        position: absolute;
        top: 24px;
        right: 14px;
        width: 106px;
        height: 44px;
        line-height: 44px;
        border-radius: 20px;
        background: #fff;

        .skip-time {
            margin-right: 2px;
        }
    }

    // 底部log
    .logo {
        position: absolute;
        left: 0;
        bottom: 64px;
        width: 100%;
        font-size: 48px;
        color: #fff;
        // 使用动画
        animation-name: fadeUp;
        animation-duration: 3s;
    }

    // 动画：从上往下淡入
    @keyframes fadeUp {
        from {
            opacity: 0;
            bottom: 128px;
        }

        to {
            opacity: 1;
            bottom: 64px;
        }
    }
}